Simplified test of universality in lattice QCD

A simplified test of universality in lattice QCD is performed by analytically evaluating the continuous Euclidean time limits of various lattice fermion determinants, both with and without a Wilson term to lift the fermion doubling on the Euclidean time axis, and comparing them with each other and with the zeta-regularized fermion determinant in the continuous time-lattice space setting. The determinant relations expected from universality considerations are found to be violated by a certain gauge field-dependent factor; i.e., we uncover a universality anomaly. The physical significance, or lack thereof, of this factor is a delicate question that remains to be settled.